Performance of AT91SAM7S64 usb port

Hi,
I'm running usb-device-cdc-serial-project-1.2-at91sam7s-ek
on my board, the performance is very low, far away from
1MByte/S, as datasheet said.
I guess maybe problem is the code call CDCDSerialDriver_Read
in main loop, and this is not running fast enough?

So there are another problem, I'm using yagarto-tools, which
is arm-elf-gcc and Eclipse, how can I chang Makefile or link
script to make function main() running in sram?

Regards,
Yanjun Luo. Start a New Thread

Hi,

Thanks for your reply, it's really a bad news for me:-(
I'll try to find a best result.

Regards,
Yanjun Luo.

----- Original Message -----
From: Foltos
To: A...
Sent: Thursday, February 14, 2008 10:33 PM
Subject: Re: [AT91SAM] Performance of AT91SAM7S64 usb port
Hi,

the latency of USB is very high (1 mS). Don't expect to get high speed if
you transfer a lot of small data chunks.

Foltos

Yanjun Luo wrote:
Hi,
I'm running usb-device-cdc-serial-project-1.2-at91sam7s-ek
on my board, the performance is very low, far away from
1MByte/S, as datasheet said.
I guess maybe problem is the code call CDCDSerialDriver_Read
in main loop, and this is not running fast enough?

So there are another problem, I'm using yagarto-tools, which
is arm-elf-gcc and Eclipse, how can I chang Makefile or link
script to make function main() running in sram?

Regards,
Yanjun Luo. Start a New Thread

Hi,

the latency of USB is very high (1 mS). Don't expect to get high speed
if you transfer a lot of small data chunks.

Foltos

Yanjun Luo wrote:
>
> Hi,
> I'm running usb-device-cdc-serial-project-1.2-at91sam7s-ek
> on my board, the performance is very low, far away from
> 1MByte/S, as datasheet said.
> I guess maybe problem is the code call CDCDSerialDriver_Read
> in main loop, and this is not running fast enough?
>
> So there are another problem, I'm using yagarto-tools, which
> is arm-elf-gcc and Eclipse, how can I chang Makefile or link
> script to make function main() running in sram?
>
> Regards,
> Yanjun Luo.
>
> Start a New Thread